Irradiation apparatus



July 17, 1934.

G. P. GOODE UIRRADIAITION APPARATUS Filed Sept. 24, 1931 5 Sheets-Sheet 2 Patented July 17, 1934 IRRADIATION APPARATUS Godfrey General Development P. Goode, Covington, Ky., assignor to Laboratories, Inc., New

York, N. Y., a corporation of Delaware Application September 24, 1931, Serial No. 564,957 15 Claims. (CI- 99-11) diant energy begin at well defined critical wave lengths and continue for shorter wave lengths at which absorption takes place. Controlled irradiation therefore requires control of the wave lengths of the radiant energy and this can be accomplished most suitably by filtering the light through suitable filters which donot transmit undesired wave lengths. The most convenient and suitable filters for general usage are liquid solutions and these usually need to be circulated .in order to prevent heating and also changes in their filtering characteristics due to unduly prolonged exposure to the radiant energy.

One of the objects of the present invention is to provide irradiation apparatus embodying a source of radiant energy and suitable filtering media and arranged so 'that any one of several filtering media may be employed with the source 'of radiant energy.

Another object is to provide irradiation apparatus embodying means whereby a plurality of substances may be irradiated at the same time each through a selected filtering medium.

A further object is to provide a unitary irra diation apparatus embodying a source of radiant energy, the necessary electrical equipment and filtering equipment, and a supply of various filtering media, all combined to constitute .a unitary irradiation unit.

One of the difliculties heretofore encountered in constructing irradiation apparatus has been the provision of filter cells for the liquid filter solution. When ultra-violet light is to be used, the most suitable medium for filter cells is quartz glass. Quartz glass, however, has an extremely low coefficient of expansion and cannot be secured'rigidly to a metallic or other rigid frame without cracking or breaking on changes intemperature because of the difference in coefiicients of expansion of the materials. 7

Another object of the invention is accordingly to provide a novel construction for liquid filter cells to be used in the irradiation apparatus.

A further object is to provide a liquid filter cell embodying novel means for obtaining a liquidtight joint between a quartz glass plate and a frame of metal or other material.

One embodiment of the invention has been illustrated in the accompanying drawings, but it is to be expressly understood that said drawings' are for purposes of illustration only and are not to be construed as a definition of the limits of the invention, reference being had to the appended claims for this purpose.

In the drawings:

Fig. 1 is a side elevation of an irradiation apparatus embodying the invention;

Fig. 2 is a view taken from the right-hand side of Fig. 1; c

Fig. 3 is a plan view of the apparatus shown in Fig.1;

Fig. 4 is an enlarged side view of a light source equipped with filter cells;

Fig. 5 is a plan view of Fig. 4;

6 is an end view of the right-hand end of 18- Figs. 7 and 8 are detail views of means for supporting a light source;

Fig. 9 is a plan view of a filter cell;

Figs. 10 and 11 are respectively side and end views of Fig. 9;

Fig. 12 is a section on the line 1212 of Fig. 14;

Fig. 13 is a section on the line 1313 of Fig. 12;

Fig. 14 is a section on the line l414 of Fig. 12;

Fig. 15 is a section on the line 15-15 of Fig. 9;

Fig. 16 is a detail view of a part of the filter cellframe; and I I Fig. 1'7 is a sectionon the line 1717 of Fig. 16. Referring now to Figs. 1 to 3, inclusive, the

irradiation unit comprises a framework of any suitable type which as shown includes corner posts 1 interconnected by cross members 2. Preferably the lower portion of the structure is enclosed to provide a cabinet having doors 3 for housing suitable electrical equipment such as rectifiers, transformers and the like, and the top of the cabinet constitutes a table 4 on which substances to be irradiated may be placed.

The upper part 5 of the unit is preferably enclosed to constitute a housing or receptacle for filtering media. In the form shown, this portion. 5 is divided into three tanks 6, '7, and 8 in which v difierent filtering solutions are held, each tank being preferably provided with suitable means such as a gauge glass 9 for indicating the amount of filter solution therein. The upper portion of the unit may also be provided, if desired, with a watch or clock 10 and a current measuring device 11.

In the space between the cabinet in the lower ed a source of radiation of any suitable type, for example, a mercury arc lamp indicated generally in Figs. 1 and 2 at 12. The radiation source may be mounted in any suitable manner, as by a framework 13 extending from the upper portion 5 of the irradiation unit. Associated with the radiation source are a plurality of filter cells, preferably constructed as hereinafter described. In the form shown, lamp 12 is open at two sides and at its bottom and filter cells 14, 15 and 16 are positioned at each of the open sides in the lamp. The filter cells may be mount ed in any suitable manner, as by securing them to the lamp itself, and each of the filter cells 14;

15 and 16 is connected with one of the tanks 6, 7, 8 by means of pipes 17, 13 and 19. After flowing through the filter cells, the filter solutions are conducted away by outlet pipes 20, 21 and 22 which preferably terminate in spouts discharging into a cup 23 and drain 24 mounted on the outside of the cabinet so that the circulation of the filter solutions may be observed. The flow of the various filter solutions may be controlled in any suitable manner, as by valves 25 in the feed pipes 1'7, 18 and 19. Preferably a water circulation is also provided for a purpose hereinafter described and to this end a water supply pipe 26 and control valve 2'7 are provided to conduct water to the filter cells and an outlet pipe 28 conducts the water away from the filter cells and discharges into the cup 23.

The lamp 12, to which the filter cells 14, 15 and-16 are preferably secured as stated above, is shown in detail in Figs. 4 to 8, inclusive. The lamp casing may be of any suitable type and is preferably closed at its top and ends but open at both sides and bottom except for the filter cells 14, 15 and 16, these cells being secured to the lamp casing in any suitable manner as by means of angle brackets 29 and thumb nuts 30 whereby the cells may be readily removed. Within the casing is a frame 31 (Figs. 4 and 7) that is pivoted at 32 to the casing. A downwardly and laterally extending portion 33 of the frame 31 is preferably forked at 34 to engage the neck of a quartz glass tube 35 having therein a pool '36 of mercury that is provided with suitable electrical connections (not shown) whereby said tube constitutes a mercury vapor arc lamp. The opposite end of this tube 35 is engaged and held by a clamp 37 (Figs. 4 and 8) that is secured to the frame 31 and comprises a pair of depending arms having clamping jaws 38 which may be clamped about the tube 35 by means of a bolt 39 and thumb nut 40. The frame 31 may be swung about its pivot 32, so as to tilt the tube 35 for starting the are, by manipulation of a suitable handle 41 that is secured to one end of the frame 31. The radiation from the arc in tube 35 accordingly passes outwardly through the two sides and bottom of the lamp casing through the filter cells 14, 15 and 16.

One form of filter cell is shown in detail in Figs. 9 to 1'7, inclusive, this cell embodying a framework carrying spaced quartz glass plates between which the filter solution circulates. Since all three filter cells 14, 15 and 16 are alike, a description of cell 16 will suffice for all. The main frame member 42 may be of metal or other suitable material and is of a shape and sizecorreportion of the unit and the filter tanks is mountspace for the circulation of filter solution. The filter cell is subject to variations in temperature due to the heat absorbed from the radiations, and

in order to prevent damage to the glass plates on changes in temperature it is desirable to cool the inner surface of the metal framework by means of a water circulation and at the same time to seal the plates to the framework by a material capable of yielding t0 permit relative expansion and contraction between the metal frame and glass plates. Moreover, ordinary quartz glass plates have an uneven, wavy surface. In order to use a gasket for sealing these plates to the frame, quartz plates having a fiat ground and polished surface must be employed, whereas the sealing means hereinafter described makes it possible to use the relatively inexpensive wavy surface quartz plates. In the form shown, the frame 42 has secured thereto in any suitable manner an auxiliary frame 45 provided with a notch or shoulder 45' which receives the outer quartz glass plate 43. The frame portions 42 and 45 may for example be secured together by means of screws 46, a gasket 46' being preferably interposed between them. This frame is preferably cooled by providing a channel adjacent the irmer surface thereof and circulating cooling water or other cooling medium therethrough. Referring to the drawings, a channel member 47 is secured in any suitable manner to the inner face of the frame '42. At one end of the filter cell, inlet and outlet openings 48 and 49, respectively, are tapped in the frame 42 and passages 50 and 51 extend from said openings to the inner face of the frame and communicate with the channel within the member 4'7. The cooling medium may be caused to circulate from the opening 48 around the channel 47 and back to the opening 49 by any suitable means such as a projection 52 formed on the frame member 42 and closing the channel 47 between the openings 48 and 49.

As clearly shown in Fig. 13, the frame member 42 is provided with a shoulder or notch 53 in which the inner glass plate 44 is seated, similar to the notch or shoulder 45' in which the outer plate 43 is seated. The plates are held in position and a liquid-tight seal is formed by means'of a suitable yielding cemental substance 54 such as tar or the like which is fllled in the corners formed in one case by the channel member 47, frame member 42 and glass plate 44 and in the other case by the frame member 45 and plate 43. The sealing material is preferably sufficiently yielding to permit slight relative expansion and contraction between the plates and frame members and any heat which may be absorbed is conducted away by the water cooled channel member 47. 1

The filtering solution is conducted to the filter cell by means of the supply pipe 19 and means are provided whereby the solution is caused to enter the cell at a plurality of points spaced across its entire end, so as to provide a complete circulation throughout the cell and to avoid eddies and the like. In the form shown, one end of the frame member 42 is provided with a groove 55, and the inlet pipe 19 is secured in an opening 56 in the end of the frame member which communicates with the groove 55. The inner side of the groove is closed by a plate 57 of any suitable material which plate is provided with a plurality of openings 58. Filtering solution enters the groove through the pipe 19'and passes 1 solution through the cell.

formly across the cell. The filter solution is discharged at the other end of the filter cell through an opening 59 formed in the frame 42 and having an enlarged portion 60 in which the outlet or discharge pipe 22 may be secured. The size of the opening 59 may be suitably restricted in order to control the rate of circulation of the filter Where the filter cell is positioned in a vertical plane as in the case of cells 14 and 16, the discharge outlet 59, 60 should be formed adjacent the lower corner of the cell as clearly shown in Fig. 9.

While connections may be made separately from the water supply pipe 26 to the individual filter cell, it is preferred to circulate the water continuously or in series through the cooling passages of the three cells. Referring now to Figs. 4, 5 and 6, the supply pipe 26 is connected as shown with the inlet opening 48 of cell 14, circulates through the cell 14, and is discharged into a pipe 61 connected to the inlet opening 48 of the cell 16. The water from the outlet opening 49 of cell 16 is conducted by a pipe 62 to the inlet opening 48 of cell. 15, and discharges from the outlet'opening 49 of cell 15 into the discharge pipe 28. Thusthe circulating water from supply pipe 26 flows first through cell 14, then through cell 16, then through cell 15, and then through discharge 28 into the'cup 23. Any stoppage of the circulating passages in the entire system will immediately be indicated by stopping of the water discharged into the cup 23. It will be understood, however, that the arrangement of pipe connections to the various cells may be varied as desired so that the water circulates therethrough in cfifierent order or that separate connections may be provided from the supply pipe 26 to each of the cells and separate discharge pipes from each of the cells to the common discharge pipe 28.

When it is desired to use the irradiation apparatus, current is first turned on by means of a suitable switch 63 in the cabinet and an arc is caused to strike within the bulb 35 by tilting the frame 31 by means of handle 41. As soon as the arc strikes, a source of ultra-violet light is provided, irradiation passing outwardly through the two open sides of the lamp housing and through the open bottom thereof. The tanks 6, '7 and 8 are filled with suitable filtering solutions. If it is desired to irradiate with a solution having the characteristics of' the solution in tank 6, the valve 25 in pipe 17 is opened and filter solution passes by gravity through pipe 17 and into the filter cell 14 from which it is discharged through pipe 20 into the cup 23 and drain 24. Failure of liquid to discharge from the proper spout into cup 23 indicates that the solution is not fiowing through the cell. At the same time valve 27 in water supply pipe 26 is opened and cooling water flows through cell 14 andthe other cells in series, discharging from pipe 28 into the cup 23. The substance to be irradiated is then placed-at the side of the lamp adjacent the cell 14 inany suitable manner. If it is desired to use either cell 15 or 16 or both, filter solutions from tanks 7 and 8 are supplied to these cells in the same manner. Thus any substance to be irradiated may be irradiated with light passing through any one of the three filter solutions in tanks 6, '7 and. 8 and three substances may be irradiated at the same time. Obviously, the number of filter solutions may be increased and suitable connections provided whereby more than one liquid may be conducted to any one of the three filter cells, or the lamp may be provided with more than three filter cells.

rality of filter cells The apparatus above described provides an irradiation unit which has many advantages where any extensive irradiation work is to be done. For example, when testing the effect of irradiation on various substances and with various wave lengths, the apparatus not only.v

makes it possible to conduct a plurality of steps at the same time, but all of the necessary equipment is assembled in a unitary apparatus and ready for use. The assembly of the equipment in an apparatus of the type described results in saving of space, extension of usefulness of a lamp, saving in time and labor, etc.

Filter cells of the type described above provide for a continuous circulation of the filter solution and at the same time insure an evenly distributed flow "of the filter solution throughout the cell whereby eddies and the like are prevented. Heating of the metal frame of the cell is prevented by the circulation of cooling water adjacent the inner surface of the metal frame member. This circulation not only carries off the heat absorbed from the radiation of the are, but also-cools the yielding sealing material. The cooling of the metal frame and the use of the yielding seal between the metal frame and the quartz glass plates render it possible to contruct a filter cell comprising a framework carrying parallel spaced quartz glass plates without cracking or breaking of the plates, and also to use the relatively inexpensive wavy surface plates without grinding or polishing.

, It will be understood that the invention is not limited to the form described and illustrated in the drawings and that changes may be made in the form, details of construction and arrangement of parts-without departing from the spirit of the invention. Moreover, the invention is not limited to apparatus designed for irradiation with ultra-violet light but may be employed for irradiation with other forms of radiant energy. The number of filter solution tanks, and the number and arrangement of filter cells, may be varied in any suitable way to meet desired conditions, and as regards many advantages of the invention, any other suitable type of filter may be employed. Reference is, therefore, to be had to the appended claims for a definition of the limits of the invention.

What is claimed is:

1. Irradiation apparatus comprising in combination a frame, a source of radiant energy mounted thereon, a plurality of containers for liquid filter media carried by said frame, a plurality of filter cells positioned adjacent said source of radiant energy, and means for CiI'CLIIEt-,

ing filtering liquid from said containers to said cells, whereby radiations from said source may be simultaneously filtered through a plurality of different filtering media.

2. Irradiation apparatus comprising in combination a frame, a source of radiant energy mounted thereon, a plurality of filter cells associated with said source, a plurality of receptacles for liquid filter media carried by said frame, connections between said receptacles and filter cells whereby the filter media may be circulated from said receptacles through said filter cells, and valve means for controlling the circulation of the filter media independently. v

3. Irradiation apparatus comprising 'in combination a frame, a source of radiant energy mounted thereon, a plurality of containers for liquid filter media carried by said frame, a plupositioned adjacent said source of radiant energy, means for circulating filtering liquid from said containers to said cells,

.bination a frame, a source of radiant energy mounted thereon, a plurality of filter cells associated with said source, a plurality of receptacles forliquid filter media carried by said frame, connections between said receptacles and filter cells whereby the filter media may be circulated from said receptacles through said filter cells, valve means for controlling the circulation of the filter media independently, and means whereby the circulation of filter media may be observed.

5. Irradiation apparatus comprising in combination a frame, a source of radiant energy mounted thereon, a plurality of filter cells associated with said source and having passages for circulation of a cooling medium, a plurality of receptacles for filter media, means for circulating the filtering media from said containers through said filter cells, and means for circulating a cooling medium through said passages.

6. Irradiation apparatus comprising in combi nation a frame, a source of radiant energy mounted thereon, a plurality of filter cells associated with said source and having passages for circulation of a cooling medium, a plurality of receptacles for filter media, means for circulating the filtering media from said containers through said filter cells, means for circulating a .cooling medium through said passages, and means whereby the circulation of said filtering media and of said cooling medium may be observed.

7. Irradiation apparatus comprising a frame, a source of radiant energy carried by said frame, a plurality of filter cells adjacent said source, containers carried by said frame for filtering media, means for circulating said filtering media through said cells, and a cup carried by the frame, the outlets from said filter cells discharging into said cup.

8, Irradiation apparatus comprising a frame, a source of radiant energy carried thereby, a plurality of filter cells adjacent said source, containers carried by said frame for filtering media,

means for circulating said filtering media through said cells, said cells having passages for the circulation of a cooling medium, means for circulating a cooling medium through said passages, and a discharge cup carried by the frame, the outlets from said filter cells for filtering media and cooling medium discharging into said cup.

9. Irradiation apparatus comprising a frame, a cabinet fdrmed in the lower portion of said frame, containers for filter media carried in the upper portion of said frame, a source of radiant energy carried by said frame in the space between said cabinet and containers, a plurality of filter cells adjacent said source, and means for circulating filtering media from said containers to said cells, whereby light from said source may be si-- -medium.

11. In apparatus of the class described, a filter cell comprising a metal frame, a passage for the circulation of cooling medium formed entirely in said frame adjacent one of its surfaces and extending about the periphery thereof, a quartz glass plate carried by said frame adjacent said one surface, a yielding sealing means sealing the joint between said quartz glass plate and said frame and positioned adjacent said cooling passage, and a second quartz glass plate secured to the other side of said fram v 12. In apparatus of the class described, a filter cell comprising a frame, spaced translucent plates secured thereto and constituting therewith a filter cell, inlet and outlet passages fora filter medium, and a distributing plate adjacent said inlet passage having a plurality of spaced openings through which said filter medium'is admitted to said cell in a uniformly distributed manner.

13. In apparatus of the class described, a filter cell comprising a substantially rectangular frame, spaced translucent plates secured thereto and constitutingtherewith a filter cell, an inlet passage for filter media extending across one end of said cell and having as one side thereof a distributing plate in which are formed a plurality of spaced openings for admitting the filter media to said cell in a uniformly distributed manner, and a restricted outlet passage at the other end of said cell, said distributing plate and restricted outlet passage cooperating to control the circulation of said media through the cell.

14. In apparatus of the class described, a filter cell comprising a frame, spaced translucent plates secured thereto and constituting therewith a filter cell having inlet and outlet passages for filter media, a yielding cemental medium sealing one of said plates to said frame and forming a liquidtight joint, and means for cooling said cemental medium comprising a fluid circulating chamber housed entirely within said frame and extending therearound adjacent said sealed joint.

15. In apparatus of the class described, a filter cell comprising a frame,spaced translucent plates secured thereto and constituting therewith a filter cell having inlet and outlet passages for filter media, said frame having a passage for a cooling medium formed'therein adjacent one surface and extending about the periphery thereof adjacent the joint between said frame and one of said plates-means for circulating a cooling medium through said passage, and a yielding cemental material sealing said-joint adjacent said cooling passage and forming a liquid-tight joint.

' GODFREY P. GOODE.

its 

